Chaeles h



C. H. KINGSTON.

Throat-Gear for Gaffs.'

Pa1en1-dApra\20,1875.

NoA 162,291.

j 1143: afrpaj l @agay di@ if THE GRPHT CO.PHOTDLITH.39 BMM PARK PLACEJLY.

CHARLES H. KINGSTON, OF WORCESTER, MASSACHUSETTS, ASSIGNOR OF OSE-THIRD HIS RIGHT TO BERTRAND W. STONE, OF SAME PLACE.

IMPROVEMENT IN THROAT-GEARS FOR GAFFS.

Spccication forming part of Letters Patent No. 162,291, dated April 20, i875; application filed March 13, 1875.

To all whom it may concern Be it known that I, CHARLES H. KINGSTON, of thecity and county of Worcester, and State of Massachusetts, have invented certain new and useful Improvements in Throat-Gear for Sail-Gaifs; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, which form a part of this specification, and in Which- Figure l represents a side view of such parts of a sail-rigging as are necessary to illustrate my invention. Fig. 2 represents a face view of my improved throat-gear. Fig. 3 represents a plan view of the same; Fig. 4, a central section parallel with the axis of the gait', and Fig. 5 a central section of the throatroll.

My invention consists in the improved mechanism hereinafter described, for the purpose of sustaining the throat of booms or against the masts of vessels upon which foreand-aft sails are employed.

In the drawings, A denotes the mast. B indicates the gaft'or boom; C, the jaws, D, the throat-halyards; E, the peak-halyards, and F the sail, all of which parts may be constructed and arranged in the ordinary manner, and therefore require no further description.

At the inner end of the gaff B, (which is beveled, as at b b,) and between the jaws C, is arranged the rocker-block G. Thei'ace of this block I form with backward bevels a x at its upper and lower ends, with a straight portion, c, between'said bevels. (See Figs. 2 and 4.) I also provide a bearing-roll, I, which is ar-l ranged in a recess in the block centrally between the beveled surfaces a x, and supported by a bolt or spindle, K, extending transversely through the jaws, as illustrated. This bolt K also supports the rocker-block G, and both the roll and block are hung loosely upon the bolt. The roll I is so placed in relation to the face of the block G that the bearing-face of the roll projects at the front or Straight portion c ot' the block, but is back of the planes of the beveled surfaces am 5 or, in other words, the bearing-face of roll I is near the center of the triangular space included by the intersection of three planes coincident with the several surfaces or faces a x c on the block G. The back ot' the block G is formed straight, and the parts are arranged so that the block will rock squarely against the bevels b b on the gatt'end.

The operation ot' the device is as follows: The sail F, while being hoisted, is raised with the throat-halyards D in advance of the peakhalyards E, so that the ga B, while going up, hangs somewhat near a horizontal position, or with its outer end depressed, (see Fig. 4,) and the block G, rocking loosely, allows the roll I to travel against the mast A, and sustain the entire pressure and friction at the throat of the gaft, which, with large sails and heavy rigging, is quite severe. `But the roll I, turning smoothly on its bolt K, reduces the friction to the minimum, and permits t-he throat to move along the mast with but a slight resistance. When the sail has been thus raised to position, the peakhalyards E are drawn taut, and the outer end ot' the gat't' raised for straining the peak ot' the sail, and the inclination thus imparted to the gaft' ('see Fig. l, and dotted lines in Fig. 4) causes its upper corner to press forward the top ot' the rocker G, relieving the roll I, and bringing the bearing against the mast A upon the upper beveled surface a, while the bevel b of the gaff rests squarely against the back of said block G. By thus transferring the bearing from the roll I to the surface a of the block G, a long, smooth bearing is provided against the mast, and the roll I is prevented from wearing into the mast as the gai' sways back and forth with the motion ofthe vessel.

The roll I may be made as in Fig. 5, with metal end bushings m and guard-plates 0, or in other suitable manner, as preferred, and the tace ot' the roll can be formed straight or concaved, and be covered and protected by rubber or other material, it' desired.

The roll I can be placed at any desired position in the block, the planes of the beveled surfaces being made to correspond, or so that when the bearing comes onto said surfaces the roll will be relieved.

The bolt K may," if desired, be heldin bea-rjaws C.

The roll I may be used with a flat block or bearing-surface rigid with the gai'; but I prefer the foim shown.

Having described my improved throat-gear for sail-gas, Wha/c I claim as new and of my invention, and desire to secure by Letters Patent, is

The combination, ivith the mast A and gaff B, of a flat-bearing surface and a bearing-roll, arranged in suoli relation to each other tha-b the operation of peaking the gaff or elevating its rear end will transfer the pressure or suain at the throat from the bearing-roll to the flat bearing-surface, and vice versa, for the purpose set forth. CHARLES H. KINGSTON.

"tnessesz GHAs. H. BURLEIGH, JOHN P. KINGSTON. 

